1. Field of the Invention
This invention resides in an improved disc-type brushless alternator having increased efficiency and reduction in energy loss, for example electricity. The alternator has increased surface area with surfaces not perpendicular to or in line with the axis of said alternator. The alternator has a reduced air gap loss with the increased surface area of the portion of said rotors and stators which face each other. It should be noted that the disc-type brushless alternators herein may contain a plurality of rotors and stators. This improved disc-type brushless alternators when having an air gap defined by serrated surface areas on the rotors and stators, have reduced magnetic pull on the bearings because of the different angles on the stator and rotor surfaces.
In induction type machines, the power output of said machines depends upon a produced magnetic flux that crosses an air gap between a rotor and stator contained in said machine.
In a disc-type brushless alternator, EMF produced by said machine is directly proportional to the power transferred by rotating fluxes produced between rotors and stators contained in said machine and having air gaps there between. If the air gaps or the air gap flux densities between the surface areas of the rotors and stators are too large, a large loss in ampere turns is noted and the field coil will have sufficient currents and turns.
In the past, others have tried to solve the energy loss across the air gap in disc-type machines by increasing the rotor and stator outside diameters, and by increasing the length of the rotor and stator sections for cylindrical air gap machines. These two approaches have the disadvantage of requiring a larger machine.
In the alternative, cylindrical air gap machines have used slip rings with brushes and brush holders to conduct current to the field coil. This type machine suffers from the disability of having a voltage drop across the brushes during use. The brushes in these types of machines also have a limited life due to the wear on the rotating slip rings.
2. Description of the Prior Art
Numerous attempts have been made in the past to increase the efficiency and reduce the energy consumption of disc-type electric machines.
For example, U.S. Pat. No. 3,296,475 to Parker relates to dynamo-electric machines, and rotors therefor. In particular, the patent describes an axial air gap machine having a lower rotor resistance thereby reducing power losses in said machine.
U.S. Pat. No. 3,304,450 to Bask, Jr., et al., describes an axial air gap dynamoelectric machine, wherein said machine is brushless and contains a rotor spaced apart from a stator armature by an axial air gap. A rotor disc, as described above, has at least one of its sides juxtaposed to a stator core provided with an armature winding with a narrow axial air gap between the faces of the stator and of the rotor.
U.S. Pat. No. 3,581,389 to Mori, et al., discloses a method for producing a magnetic core for an electric rotating machine which has an axially spaced air gap as in the case of a disc-type rotating machine.
U.S. Pat. No. 4,207,487 to Beyersdorf describes a disc-type, dynamo-electric machine having two stators and one rotor, active air gaps between each stator and the rotor, two annular energizing windings in the stators, and two non-active or auxiliary air gaps formed in a smooth region between the stators and the rotor.
U.S. Pat. No. 5,093,596 to Hammer relates to a combined linear-rotary direct drive step motor which provides both linear and rotary motion over a predefined range, e.g. along a portion of the longitudinal axis of the rotor shaft. The rotor and stator of the rotary step motor are described as having teeth.
U.S. Pat. No. 5,177,392 to Scott discloses a disc-type machine having a plurality of alternating stator and/or rotor sections. The stator has micro-laminated stator teeth molded from cut steel particles, mounted on a large disc of composite fiber material which is the main structure component of each stator section.
U.S. Pat. No. 5,777,421 to Woodward Jr. teaches a disc-type electrical machine having enhanced efficiency and effectiveness. The machine comprises a housing unit, a stator connected to said housing unit, a shaft rotatably connected to the stator housing unit with rotation means. A rotator connected to the shaft wherein the stator surface area and the rotor surface area are serrated.
As can readily be determined from the foregoing there is an ongoing research effort and a need to develop and produce new and novel disc-type electric motors that have increased efficiency, is economical and easy to manufacture.